Syntheses of some polyunsaturated trifluoromethyl ketones as potential phospholipase A(2) inhibitors

Starting from (all-Z)-icosa-5,8,11,14,17-pentaenoic acid [(all-Z)-eicosa-5, 8,11,14,17-pentaenoic acid, EPA] and (all-Z)-docosa-4,7,10,13,16,19-hexaeno ic acid (DHA) several trifluoromethyl ketones, containing sulfur or oxygen atoms at the beta-position, have been synthesized as potential inhibitors o f cytosolic phospholipase A(2). As part of this work EPA and DHA have been oxidatively degraded to (all-Z)-pentadeca-3,6,9,12-tetraenal and (all-Z)-oc tadeca-3,6,9,12,15-pentaenal, respectively, in 75% overall yields.